
All the railings combined probably total less than 20 pounds.
Iron Chief is a bit deceiving, it looks top heavy, but it isn't. The wood in the cabin sides is only 3/8" thick. The cabin roofs are 1/2" thick. The hull weighs around 1500 pounds and the Engine and boiler are roughly another 1500 pounds. Plus it has an 8' beam. I'm guessing the total weight to be somewhere around 4500 to 5000 pounds and 75% of that is below the gunwale. This style hull/boat was never intended for rough water although they handle it quite well.
There are some interesting and informative articles around the web on hull stability. The common practice or thought on improving stability is to add weight low, that is accurate, but incomplete. Adding any weight to a multi-chined hull and others, even above the gunwale within reason, improves stability. The deeper the hull sits in the water the displacement is increased -center of buoyancy is raised and there is more wetted hull surface/shape working towards greater stability. Pointing to some of these cruise ships, looking at them straight on, they appear to defy physics. The designers have added enough weight for the hull to work properly. More weight makes it a bigger hull in the water. Where this is really noticeable, when I there are ten er so people aboard. Someone steps on the gunwale, it doesn't budge.
Here is a video in some rough water and we went out further and the waves got even bigger and we ran them on the same tack. It rocked around pretty good, but any 22' boat would. It went down on the rails a few times and always came back.
-Ron